Problem: Evaluate the following expression when $a = 2$ and $b = 5$. $3$ $a$ $ + 4$ $b$ $ + 8$
Solution: Substitute $2$ for ${a}$ and $5$ for ${b}$ $ = 3{(2)} + 4{(5)} + 8 $ $ = 6 + 20 + 8 $ $ = 34$